Pulmonary hypertension in chronic obstructive pulmonary disease: current understanding, knowledge gaps and future directions.

PURPOSE OF REVIEW: Despite the advent of effective and mechanistically diverse treatments for pulmonary arterial hypertension (PAH) and their positive impacts on the functional capacities and outcomes for PAH patients, the much larger population of patients with pulmonary hypertension (PH) in chronic lung diseases like chronic obstructive pulmonary disease (PH-COPD) remain without effective therapies. RECENT FINDINGS: In this review, we will highlight advances in the understanding of PH-COPD pathobiology, the clinical impact comorbid PH has on COPD outcomes, and detail the spectrum of disease and clinical phenotypes that encompass the heterogenous disease manifestations of PH-COPD. Finally, we will examine recent studies exploring the effects of potential treatments for PH-COPD and highlight sub-populations and treatment options that warrant further study. SUMMARY: As the PAH population-base ages and comorbid diseases become more frequently diagnosed in PAH patients, the need to clearly delineate subpopulations for clinical applications of PH therapies and research becomes even more urgent. Through an improved understanding of the clinical phenotypes of PH-COPD and the overlap with certain subpopulations of PAH, a framework for future research and potential for therapeutic impact is highlighted.

Tocilizumab Is Associated with Increased Risk of Fungal Infections among Critically Ill Patients with COVID-19 and Acute Renal Failure: An Observational Cohort Study.

RESEARCH QUESTION: Does treatment with tocilizumab increase the risk of a fungal infection in critically ill patients with coronavirus-19? BACKGROUND: Numerous therapies have been evaluated as possible treatments for coronavirus-2019 caused by severe acute respiratory syndrome coronavirus-2. Tocilizumab is a humanized monoclonal antibody directed against the interleukin-6 receptor that has found a role as a therapy for patients with severe coronavirus-19 pneumonia. The immunomodulatory effects of tocilizumab may have the unintended consequence of predisposing recipients to secondary infections. We sought to assess the risk of invasive fungal disease and the therapeutic impact of tocilizumab on the hospital length of stay, duration of mechanical ventilation, and intensive-care-unit length of stay in critically ill patients with severe coronavirus-19 pneumonia. METHODS: Records of critically ill patients with coronavirus-2019 admitted from March to September 2020 at our institution were reviewed. The risk for fungal infections, intensive-care-unit length of stay, hospital length of stay, and duration of mechanical ventilation in those that received tocilizumab in addition to standard coronavirus-2019 treatments was assessed. RESULTS: Fifty-six critically ill patients treated with dexamethasone and remdesivir for coronavirus-2019 were included, of which 16 patients also received tocilizumab. The majority of the cohort was African American, Asian, or of other ethnic minorities (53.6%). Invasive fungal infections occurred in 10.7% of all patients, and infection rates were significantly higher in the tocilizumab group than in the control group (31.2% vs. 2.5%, risk difference [RD] = 28.8%, p < 0.01). The increased risk in the tocilizumab group was strongly associated with renal replacement therapy. There was a dose-response relationship between the risk of fungal infection and number of tocilizumab doses received, with 2.5% of infections occurring with zero doses, 20% with a single dose (RD = 17.5%), and 50% with two doses (RD = 47.5%) (trend test p < 0.001). In addition, ICU LOS (23.4 days vs. 9.0 days, p < 0.01), the duration of mechanical ventilation (18.9 vs. 3.5 days, p = 0.01), and hospital length of stay (LOS) (29.1 vs. 15.5, p < 0.01) were increased in patients that received tocilizumab. CONCLUSIONS: Repurposed immunomodulator therapies, such as tocilizumab, are now recommended treatments for severe coronavirus-2019 pneumonia, but safety concerns remain. In this early pandemic cohort, the addition of tocilizumab to dexamethasone was associated with an increased risk of fungal infection in those that were critically ill and received renal replacement therapy. Tocilizumab use was also associated with increased ICU and hospital LOSs and duration of mechanical ventilation.

Ageing and chronic obstructive pulmonary disease: interrelationships.

PURPOSE OF REVIEW: As life expectancy increases, the ageing population accrues an increasing burden of chronic conditions and functional compromise. Some conditions that lead to compromise are deemed part of 'natural ageing,' whereas others are considered to represent disease processes. Ageing ('a natural process') and chronic obstructive pulmonary disease ('a disease') share many common features, both pulmonary and systemic. At times, the pathways of injury are the same, and at times they are concurrent. In some cases, age and disease are separated not by the presence but by the severity of a finding or condition. This brief review aims to compare some of the similarities between ageing and COPD and to compare/contrast mechanisms for each. RECENT FINDINGS: At the cellular level, the natural process of ageing includes multiple systemic and molecular mechanisms. COPD, though defined by progressive pulmonary compromise, can also be a systemic disease/process. It has become evident that specific senescence pathways like p-16 and the sirtuin family of proteins are implicated both in ageing and in COPD. Also common to both ageing and COPD are increased inflammatory markers, leucocyte response abnormalities, and DNA-level abnormalities. SUMMARY: The prevalence of COPD increases with increasing age. COPD contributes to the accrued burden of chronic disease and is a significant contributor to morbidity and mortality in this population. This review attempts to summarize some of similarities between ageing and COPD and their underlying mechanisms.

Immune Checkpoint Inhibitor-Related Pneumonitis in Lung Cancer: Real-World Incidence, Risk Factors, and Management Practices Across Six Health Care Centers in North Carolina.

BACKGROUND: Immune checkpoint inhibitors (ICIs) are standard treatments for advanced non-small cell lung cancer and have expanded use in small cell lung cancer. Although generally better tolerated than traditional chemotherapy, immune-related adverse events, such as immune checkpoint inhibitor-related pneumonitis (ICI-P), remain poorly understood toxicities that limit ICI treatment and can result in considerable morbidity. In this retrospective case-control study, we assessed a lung cancer cohort to identify ICI-P risk factors. RESEARCH QUESTION: What are the risk factors, clinical presentations, radiographic findings, and outcomes for ICI-P in a real-world lung cancer cohort? Do chronic pulmonary diseases confer increased risk for ICI-P? STUDY DESIGN AND METHODS: Medical records from lung cancer patients receiving nivolumab, pembrolizumab, or combination ipilimumab and nivolumab at six centers in North Carolina were reviewed (January 2004-July 2017). Patients with ICI-P and control participants were characterized, and logistic regression was used to assess for ICI-P risk factors. RESULTS: Three hundred fifteen lung cancer patients who predominantly received nivolumab (76.5%) or pembrolizumab (22%) were included. The incidence of ICI-P was 9.5%, with a median time to diagnosis of 52.5 days. Most patients with ICI-P had cases of high severity, and eight patients (27%) died with ongoing ICI-P treatment. Development of ICI-P was independently associated with the presence of baseline fibrosis on chest CT scan (adjusted OR [aOR], 6.61; 95% CI, 2.48-17.7), a composite measure of obstructive lung disease (aOR, 2.79; 95% CI, 1.07-7.29), and treatment with pembrolizumab (aOR, 2.57; 95% CI, 1.08-6.11). INTERPRETATION: In this cohort, ICI-P was more common and severe than previously reported and carried an unexpectedly high mortality rate. Risk for ICI-P was shown to be independently associated with several chronic pulmonary diseases, which may account for the higher incidence of ICI-P in patients with lung cancer.

Treatment with a monoclonal antibody against methamphetamine and amphetamine reduces maternal and fetal rat brain concentrations in late pregnancy.

We hypothesized that treatment of pregnant rat dams with a dual reactive monoclonal antibody (mAb4G9) against (+)-methamphetamine [METH; equilibrium dissociation rate constant (KD) = 16 nM] and (+)-amphetamine (AMP; KD = 102 nM) could confer maternal and fetal protection from brain accumulation of both drugs of abuse. To test this hypothesis, pregnant Sprague-Dawley rats (on gestational day 21) received a 1 mg/kg i.v. METH dose, followed 30 minutes later by vehicle or mAb4G9 treatment. The mAb4G9 dose was 0.56 mole-equivalent in binding sites to the METH body burden. Pharmacokinetic analysis showed baseline METH and AMP elimination half-lives were congruent in dams and fetuses, but the METH volume of distribution in dams was nearly double the fetal values. The METH and AMP area under the serum concentration-versus-time curves from 40 minutes to 5 hours after mAb4G9 treatment increased >7000% and 2000%, respectively, in dams. Fetal METH serum did not change, but AMP decreased 23%. The increased METH and AMP concentrations in maternal serum resulted from significant increases in mAb4G9 binding. Protein binding changed from ∼15% to > 90% for METH and AMP. Fetal serum protein binding appeared to gradually increase, but the absolute fraction bound was trivial compared with the dams. mAb4G9 treatment significantly reduced METH and AMP brain values by 66% and 45% in dams and 44% and 46% in fetuses (P < 0.05), respectively. These results show anti-METH/AMP mAb4G9 therapy in dams can offer maternal and fetal brain protection from the potentially harmful effects of METH and AMP.

Monoclonal antibodies as pharmacokinetic antagonists for the treatment of (+)-methamphetamine addiction.

Developing specific medications to treat (+)-methamphetamine (METH) addiction is a difficult challenge because METH has multiple sites of action that are intertwined with normal neurological function. As a result, no small molecule medication for the treatment of METH addiction has made it through the FDA clinical trials process. With the invention of a new generation of proteinbased therapies, it is now possible to consider treating drug addiction by an entirely different approach. This new approach is based on the discovery of very high affinity anti-METH monoclonal antibodies (mAbs), which are non-addictive and antagonize METH effects from the blood stream without entering the brain. Due to a very long biological half-life, anti-METH mAbs would only need to be administered once every 2-4 weeks, aiding in patient compliance. As a relapse prevention medication, anti-METH mAbs could reduce or prevent the rewarding effects of a relapse to METH use and thereby improve a patient's probability of remaining in therapy and recovering from their addiction. In this review, we discuss the discovery process of anti-METH mAbs, with a focus on the preclinical development leading to high affinity anti-METH mAb antagonists.

Development and preclinical testing of a high-affinity single-chain antibody against (+)-methamphetamine.

Chronic or excessive (+)-methamphetamine (METH) use often leads to addiction and toxicity to critical organs like the brain. With medical treatment as a goal, a novel single-chain variable fragment (scFv) against METH was engineered from anti-METH monoclonal antibody mAb6H4 (IgG, kappa light chain, K(d) = 11 nM) and found to have similar ligand affinity (K(d) = 10 nM) and specificity as mAb6H4. The anti-METH scFv (scFv6H4) was cloned, expressed in yeast, purified, and formulated as a naturally occurring mixture of monomer ( approximately 75%) and dimer ( approximately 25%). To test the in vivo efficacy of the scFv6H4, male Sprague-Dawley rats (n = 5) were implanted with 3-day s.c. osmotic pumps delivering 3.2 mg/kg/day METH. After reaching steady-state METH concentrations, an i.v. dose of scFv6H4 (36.5 mg/kg, equimolar to the METH body burden) was administered along with a [(3)H]scFv6H4 tracer. Serum pharmacokinetic analysis of METH and [(3)H]scFv6H4 showed that the scFv6H4 caused an immediate 65-fold increase in the METH concentrations and a 12-fold increase in the serum METH area under the concentration-time curve from 0 to 480 min after scFv6H4 administration. The scFv6H4 monomer was quickly cleared or converted to multivalent forms with an apparent t(1/2lambdaz) of 5.8 min. In contrast, the larger scFv6H4 multivalent forms (dimers, trimers, etc.) showed a much longer t(1/2lambdaz) (228 min), and the significantly increased METH serum molar concentrations correlated directly with scFv6H4 serum molar concentrations. Considered together, these data suggested that the scFv6H4 multimers (and not the monomer) were responsible for the prolonged redistribution of METH into the serum.